Call transmitter



Oct. 9,1945. R. F. MALLINA CALL TRANSMITTER Filed Au 20, 1941 4Sheets-Sheet 1 v INVENTO R :RFMALL/NA By c9- %dfixflm ATTORNFV v &91945; T R. F. MALLINA I 8 CALL TRANSMITTER uvvavron R. F MALL/NAATTORNEY Oct. 9, 1945. R. F. MALLINA 2,386,486

CALL TRANSMITTER l Filed Aug. 20, 1941 4 Shets-Sheet 3 I INVENTOR- F/G.5R/r'MALL/NA 7 29 QJQQA ATTORNEY Patented Oct. 9, 1945 CALL TRANSMITTERRudolph F. Mallina, Hastings on Hudson,'N. YE,

assignor to Bell Telephone Laboratories; Incorporated, New York, N. Y.,a corporation of New York Application August 20, 1941, Serial No.407,520 7 Claims. 011119-90) This-invention relates to telephone calltransmitters and more specifically to call transmitters of the presettype.

The: object of the invention is the provision of a call transmitter ofthe type above referredto.

which will be simple in construction, convenient in use and positive inoperation.

According to' the present invention, a call transmitter of the typeabove mentioned is provided in which pivoted manually operablesectorshaped members having indices printed at their peripheries aremoved from normal to preset position with reference to a common stop forpositioning pulsing cam elements carried thereby for setting a call.Means. is provided for'holding each camming sector member inits's'elected'position with means manually operable to cause the releaseof the holding means of one of the sector members whereby the return ofsuch sector is effective to cause the release of all sector memberssuccessively for actuating a pulsing. contact through th operation of acommon rocking bar actuated by the successive return of. these sectormembers to normal under the tension. of their own motor springs andunder control of a governor mechanism, these springs being tensionedduring the manual operation of the sector members as for the setting ofa call, whilea normally I v closed contact is provided-for shunting thepulsing contact during theoperation of the rocking bar by the manualselectingmovement of the arcuated camming members.

Means is provided whereby the removal of the handset from the plungersin the cradle of-the handset support causes the automatic operation of amechanism for opening the shunting contact and removing alatching memberfrom the pawl which holds the manually releasable sector memher in theselected position so as to conditionin cooperation with the manuallyoperable holding means the operating mechanism for transmitting thetelephone call designation thus selected or transmitting calldesignations digit-by-digit instead of by the preset operation, manuallyoperable ineansbei'ng provided whereby the sector members mayberelea'sed so as to permit their return to normal position collectivelyfollowing the setting of a wrong telephone call designation, thusavoiding the loss of time inherent in the return movement of the pulsingsector members to normal individually under control of thegovernormechanism. w

Other novel features and' advanta'ges of the invention will appear fromthe following description andby the claims appended thereto; refer--manually operable sector non-operated position.

ence being had whichr" Fig. 1 is a to the accompanying I drawings inperspective view shown with the members in normal Fig. 2 is a left sideelevation view shown with the casing housing the transmitter mechanismin vertical ection and one of the upright sup ports for the mechanismwith portions broken wa I Fig. 3 is a horizontal sectional view taken online 3-3 of Fig. 2. I

Fig. 4 is a another left side elevation view but showing themanually'operable sector members in operated position as for the settingof a, call.

Fig. 5 is a topass'embl'yview shown withthe casing partly in horizontalsection taken on line 55 of Fig. 4 showing the sector members inoperated position. r

Fig. 6 is a front elevation view showing the easing housing thetransmitt'enmechanisrn, one of the supporting uprights for suchmechanism and a number of operating parts in section, the sector membersbeing shown in operated position.

' Fig-'7 is a partial rear-view of Fig. 6 showing the release ortransfer mechanism of the sector members, the casing being shown invertical section taken on line 1-1 of Fig. 2; and

Fig. 8 is a partial View of the sector members release mechanism shownin perspective.

As shown in the drawings, the call transmitter of the invention consistsof a base ID to which 'the upright supporting plates H an I2 are securedas by a plur'ality'of similar screws l3, and in-bearingsiormed in theseplates is journaled at both ends thereol a shaft SH provided forpivotally mounting a pl-uralityof manually operable sector members'SI;S2, S3, S4, S5, S6 and S1 3 which may vary in number according to thedigits comprised in the central oifice number. Each of the sectormembers SI, S2, S3, etc.,"is formed at its inner periphery with anarcuated row of cams I4 and on each of the sector members is secured asby a number of screws S C a dial element as l5 best seen inFigs. 1, 6and 8 preferably made of phenol plastic material having fins or fingerholds l6 provided to facilitate the manual operation of the sectormembers SI, S2, S3, etc, from normal as for setting a call which isindicated by groups of letters and digits printed at the periphery ofthe dial elements between the this 5.. Arcuated metallic strips asllhaving their ends engaging the supporting shafts I8 and H! areprovided fOr preventing frictional resistance between'the'sectormember's SI, S2, S3,

etc., while in operation, both shafts I8 and I9 being supported at theirends by the upright plates II and I2.

The manually operated sector members S I, S2, S3, etc., are held innormal non-operated position against a common stop bar 25 best seen inFigs. 2, 4 and 6 by the normal tension of their helical motor springs 20having one of their ends hooked to a common bar 2| of L-shaped crosssection secured to the upright plates I I and I2 as by a number ofsimilar screws 22 shown in Figs. 2, 3 and while the other ends of themotor springs are hooked to respective studs 23 extending from camportion 9| formed with the sector members SI, S2, S3, etc., so that thepivotal movement of these sectors from normal position as shown in Figs.1 and 2 to the operated position as shown in .Figs. 4 and 5, iseffective to tension the motor springs 20 for returning these sectormembers to normal position in a manner which will be hereinafterdescribed in detail.

The sector member SI and. its dial element I5 are normally held in eachoperated or selected position by a retaining pawl 26 engaging thecamming projections I4 of this sector as shown in Fig. 2 by the tensionof a spring 45, while a push button in the form of a plunger 26Pslidably mounted in a bushing 21 formed with a casing 28, which housesthe transmitter mechanism, is provided for imparting a small angularmovement as a unit to the arms 29 and 30 on a spindle 3| for movingthrough a connecting rod 42,

the pawl 26 on shaft 263 from the position shown in Fig. 2 to theposition shown in Fig. 4 fordisengaging it from the camming projectionsI4 of sector member SI so as to permit the return movement of thissectorto normal by the tension of its motor spring 20.

Pawl 26 as shown in Fig. 4 may beheld in the disengaged position fromthe cam projections I4 of sector SI by a latchmember in the form of abell crank lever 32. This lever is moved by the tension of spring. 32Yin abutting relation with a lug 26Y formed with pawl 26 upon the removalof the telephone handset TH from its cradle CI causing the movement ofthe plungers 39 and thereby the pivotal movement of a bar 35 on shaft 36in the direction indicated by the arrow in Fig. 2, while imparting alongitudinal movement to a rod 34 connected to the bell crank lever 32,the automatic movement of hell crank lever 32 under the tension ofretractile spring 32Y as permitted by the slot SL at the lower end ofrod 34' following the operation of plunger 26F being effective to engagethe lug 26Y of pawl 26 for holding it in the position shown in Fig. 4thereby permitting the pulsing operation of sector member SI immediatelyfollowing each selective operation as for transmitting a call by thesocalled digit-by-digit operation of the transmitter mechanism in amanner which will be hereinafter described in detail.

According to this mechanism, the placing of the telephone handset TH inits cradle as formedv by the projections PI and P2 so as to impartlongitudinal movement to plungers 39 an 40 from the position shown inFig.4 to the position shown in Fig. 2, causes the pivotal movement ofbar 35 in direction opposite to that indicated by the arrow in Fig. 2,the movement of connecting rod 34 actuating the bell crank lever 32 inthe direction indicated by the arrow in Fig. 4 for disengaging this bellcrank lever from the lug 26Y of pawl 26 which is then moved inengageable relation with one of the cam projections I4 of camming sectorSI by the tension of retractile spring 4I acting on lever unit 29-30connected as above mentioned to pawl 26 by rod 42 in addition toretractile spring 45, while the operation of bar 35 is effective toactuate the switchhook springs 4IX mounted in a pile-up arrangement on abar 42X secured to the plates II and I2 by a number of screws 43.

The sector members S2, S3, S4, S5, S6 and S1 and the dial elements I5carried thereby are retained in each selected position as defined by acommon finger stop ed formed with casin 28 by respective pawls such asP2, P3, P4, as shown in Figs. 5, 6 and 8. These pawls, together withretaining pawl 26 of sector member SI are mounted for pivotal movementon shaft 26B and like pawl 26 are normally held in engaged relation withtheir respectively associated sector members S2, S3, S4, etc. by thetension of springs 45 coiled on shaft 263 as shown in Figs. 2, 4 and 5.Pawls P2, P3, P4, etc., are disposed in operable relation with one ofthe arms of rocking members or yokes 50, 5|, 52, 53, 54 and 55 pivotedon a shaft 51 itself supported by the plates II and I2, while the otherarms of these rocking members are disposed in engageable relation withthe sector members SI, S2, S3, S4, S5 and S6 to be successively operatedthereby in the following order. Retaining pawl P2, releasing sectormember S2 is actuated by the return movement of sector member SI throughthe engagement of this camming sector with the yoke 50.

Retaining pawl P3 releasing sector member S3 is actuated by the returnmovement of sector member S2 through the engagement of this sectormember with the, yoke 5I.

Retaining pawl P4 releasing camming sector S4 is actuated by the returnmovement of sector member S3 through the engagement of this sectormember with the yoke 52.

Retaining pawl P5 (not shown) releasing camming sector S5 is actuated bythe return movement of sector member S4 through the engagement of thissector member with the yoke 53.

Pawl P6 (not shown) releasing camming sector S6 is actuated by thereturn movement of sector member S5 through the engagement of the sectormember with the yoke 54 and,

Retaining pawl PI releasing sector member S1 is actuated by the returnmovement of sector member S6 through the engagement of this sectormember with a yoke 55.

A shaft III, Figs. 1, 2, 4, 5, 6 and 7, is journalled at both ends inbearings in the upright plates II and I2 with one of its ends extendingbeyond the right side wall of casing 28 for mounting a manually operableknob I I2 provided for imparting a small angular movement to this shaftand to a bar III] carried thereby disposed transverse of the pawls 26,P2, P3, P4, etc., in engageable relation with projections such as XYshown in Figs. 2, 4 and 8 for disengaging these pawls collectively fromtheir respective sector members SI, S2, S3, etc., and thereby permittingthe return of these sectors simultaneously following the setting of awrong telephone call designation so as to avoid the delay inherent tothe successive return of the sector members SI, S2, S3, etc., to normal.a

I On the sector members SI, S2, S3, etc., are mounted spring pressedpawls 59, 60, 6|, 62, 63, 64 and '65 best seen in Fig. 3, engagingrespective ratchet wheels 69, III, II, I2, I3, I4, and I5 keyed on shaftSH for rotating the latter upon the return movement of sector membersSI, S2, S3, etc.,

to normal under the tension of their motor springs 20, the returnmovement of sector members SI, S2, S3, etc., being effected under normalcontrol of a centrifugal speed governor mechae nism CG operativelyconnected to the shaft SH by a gear 80,'keyed on one end of this shaftand actuating the pinion 01- and gear 8IA as a unit with gear BIAengaging the pinion 82 movable as a unit with gear 82A, the latterengaging a pinion 84, keyed on the shaft of the centrifugal speedgovernor CG- best seen in Figs. 2, 3 and 4, the shafts of pinion andgear units 8I--8IA and 82-82A and the shaft of speed governor CGbeing'supported at one of their ends to the upright plate; II and theirother ends by a plate 85 secured to the upright plate II by a number ofscrews 86.

A pulsing bar I20 disposed transverse of the movement of sector membersSI, S2, S3, etc., is pivoted as at I2I in the upright plates I I and I2and is held'in operative relation with the cam portions I4 of the sectormembers by the tension of an operable contact spring I22 whichcooperates with spring I23 to form a pulsing contact these springs beingmounted in a pile-up arrangement on a bracket I24 secured to the uprightplate I I as by screws I24Y.

Each sector member SI, S2, S3, etc., is, provided concentric to itsbearing portion with a camming surface as 9| serving for impartingmovement to a common bar 98 pivoted on a shaft 99 itself journaled atboth ends in plates II and I2, this bar having a projection I ofinsulating material disposed in engageable relation with the so-calledoff-normal springs I M for operating them upon the movement of the sec+tor members SI, S2, S3, etc., and holding them in the operated positionuntil all the pulsing sector elements have been returned to non-operatedposition, these springs being disposed in a pileup arrangement on abracket I02 secured to the upright disposed plate I2 as by a number ofscrews I03.

Fig. 1 to the position wherein the finger hold h j of this sector memberreaches a position registering with the finger stop ed formed by theedge of casing 28 as shown in Figs. 1, 2, 4, 5 and 6 and with thehandset TH in its cradle CI and consequently with the plungers 39 and 40in the position shown in Fig. 2, the bell crank 32 is prevented fromengaging the lug 26Y of pawl 26 which now holds the sector member SI inits selected position through its engagement with one of the pulsingprojections I4. The movement of 'sector member SI from the positionshown in Fig. 1 to the position shown in Figs. 4 and 6 causes the cam 9|of this sector to actuate the bar 98 and thereby the off-normalcontact.IOI while causing the operation of pulsing bar I20 and therebythe opening of pulsing springs I 22 and I23. The opening of thiscontact, however, is ineffective to transmit pulses due to the telephoneline being shunted by the closure of the switchhook spring pile-up M2!by the bar 35 now in position as shown in Fig. 2. I

The camming sector S2 having the letter designation Y, the second digitof the call designation WY-44321 above mentioned is moved to theposition wherein the finger hold n2 is in registry with the finger stoped where this sector member is held in the selected position by'the pawlP-2.- The sector member S3 is moved 'from' the position shown in Fig. lto the position wherethe finger hold 723 is in line relative to thefingerstop ed and in line relative to the selected position of letters Wand Y above mentioned of sector members .SI and S2, where sectormemberS3 is held in the selected position by the retaining pawl P3. The sectormember S4 is moved to the position wherein the finger hold 724 is inregistry with the finger stop ed where this sector member is held in theselected position by pawl P4 and the manual operation of sector membersS5, S6 and S1 .is effected in a manner similar to that described inconnection with sector members 5] S2, S3 and S4 that is moved inposition wherein the digits .3, 2, 1, the fifth, sixth and seventhdigits of the call designation WY- 44321 appear in registry with thecommon stop ed of casing 28 where they are retained in selected positionbypawls P5, P5, P1, not shown.

The handset TH is then removed from its cradle CI causing the upwardmovement of plungers 39 and 40, the pivotal movement of bar in thedirection indicated by the arrow in Fig, 2

for operating the shunt spring IIX and causing the longitudinal movementof rod 34 which through its slot SL frees the bell crank 32 for movementin latching position with the lug ilIiY of pawl 26 as effected by thetension of its spring 32Y. "The manual operation of plunger 2GP as forimparting a small angularmovement to the lever unit 29-30 and thereby tothe pawl 26 through the connecting rod 42 causes the disengagement ofpawl 26 from the cam projection I4 of sectormember SI so as permits thereturn movement of this sector to normal position for operating thepulsing bar I20 and the contact springs I22 and I23 for sending ninepulses, the first digit of the call designation above mentioned. Themovement of pawl 26 by plunger 26? permitting the free end of bellcrank, 32 to move under the lug 26Y of pawl 26 for holding it in, thedisengaged position relative to cam projection I4 of this sector member.

The return movement of sector member SI under the tension of its motorspring 20 is controlled by the operation of the speed governor CG asimparted by the spring-pressed pawl 59 engaging the ratchet wheel 69,see Figs. 2, 3 and 4 keyed to the shaft SH and the gear units 8I- BIAand 8282A with the gear 82A engaging the pinion 84 keyed to the shaft ofgovernor CG. It is to be noted that upon the downward movement ofplunger 261? as effected by the operator following the removal of thehandset TH from its cradle, the bell crank 32 as above mentioned wasmoved by the tension of its spring 32Y from the position shown in Fig. 2to the position shown in Fig. 4 in latching relation with the lug 26Y ofpawl 26 for holding it in disengaged position during the successivereturn movement of the sector members S2, S3, S4, etc, for a purposewhich will be hereinafter described in detail.

The return movement of camming sector SI for transmitting the ninepulses corresponding to the letter W following the operation of plunger2GP is effective upon reaching a small distance from its normal positionto engage the arm AI of yoke 50 for pivoting it and thereby imparting .asimilar movement to pawl P2 for releasing the sector member S2 which isreturned to normal position by. the tension of its own motor spring 20thus operating the pulsing bar I20 for transmitting nine pulses thesecond digit of the call designation WEI-44321. Upon the return movementof sector member S2 at a point a small distance from its normal positionthis sector member engages the yoke for operating the pawl P3 andthereby releasing the sector member S3 which is returned to normal underthe tension of its own motor spring 20, the release of the sectormembers S4, S5, S6 and S1 being effected in the" order and in the mannerabove described in connection with the release of sector members S2 andS3, for successively operating the pulsing bar I20 under control ofgovernor CG a number of times corresponding to each digit appearing inline with the finger stop ed that is 9944321, each train of pulses thustransmitted being distinguished by a lapse of time occurring during theoperation of the releasing elements of the sector members. of thehandset TH in its cradle CI, at the conclusion of the telephoneconversation the down- Ward movement of plungers 39 and 40, that is,from the position shown in Fig. 4 to the position shown in Fig. 2, iseffective to impart a pivotal movement to the bell crank lever 32against the tension of its retractile spring 32Y so as to release thepawl 26 which is then moved in position for engagement with the camprojections I4 01 sector member SI under the tension of its retractilespring 45 in addition to the spring 4! acting as above described on thelever unit 29-30 and the call transmitter mechanism is now ready for asuccessive call setting operation.

The cancelling of a telephone call designation ma be effected by therotation of the manually operable knob I I2 secured at the end of shaftI II to which the plate I In is keyed, the free edge of this plate beingdisposed in engageable relation with lugs XY of pawls 26, P2, P3,--P4,P5, P6 and P! for disengaging them simultaneously from their associatedsector members SI, S2, S3, etc., which are returned to normal by thetension of their motor springs 20 and under control of governor CG.

In the call transmitter of the invention, telephone call designationsmay be transmitted by the successive operation of sector member SI uponthe removal of the handset TH from its cradle which is followed by theoperation of the plunger 26F so as to cause the release of sector memberSI by pawl 26 which remains locked in the disengaged position by thebell crank lever 32, the disengagement of pawl 26 from camming sector SIpermitting the successive operation of this sector member fortransmitting any telephone call designation desired.

What is claimed is:

1. In a call transmitter, a plurality of manually movable arcuatedelements, each of said elements having at its inner periphery arow ofcams and indicia at its outer periphery representing digits, a pivotedbar extending transverse of the movement of said elements in operablere- Upon placing lation with said rows of cams, fin members carried byeach of said elements for-moving the latter in selected position forsetting a call, a plurality of spring pressed pawls engaging said camsfor holding said elements in said selected position, a pulsing mechanismactuated by the movement of said bar, normally closed switch springs fornegativing the operation of said bar during the setting operation ofsaid elements,

manually controlled means for operating said switch springs to renderthe operation of said elements for transmitting the call, a set ofoffnormal contacts, a bar, and means carried by said elements forcontrolling the operation of said bar for operating said 'oiT-normalcontacts.

2. In a call transmitter, arcuated elements, each of said elementshaving a plurality of pulsing cams disposed inwardly thereof, a shaftfor pivoting said elements, dials carried by said elements havingsymbols printed at their peripheries, means carried by said dialsdividing said symbols into groups and serving for moving said elementsto selected positions, a second shaft, pawls pivoted on said secondshaft for engaging said cams for holding said elements in the selectedposition, a manually operable push-button, an arm and lever unitsactuated by said pushbutton, means operatively connecting said lever toone of said pawls for moving the latter from its engaged pulsing cam forreleasing this element, spring means for returning said elements tonormal non-operated position following the operation of saidpush-button, a pivoted bar engaged by said pulsing cams during theselective and return movement of said elements, a pulsing contactactuated by the movement of said bar, means to render the movement ofsaid bar inefiective relative to said pulsing contact durin theselective movement of said elements, a third shaft, a yoke membermounted for pivotal movement on said third shaft and operated by thereturn movement of said released elements for operating the holding pawlof one ofthe other elements for releasing the latter to cause theoperation of said bar and that of said contact and a governor mechanismdriven'by each of said elements for controlling the operation of saidcontact.

3, In a call transmitter, a plurality of arouated elements having camsat their inner peripheries, finmembers at the outer peripheries of saidelements for moving the latter from normal to selected position, meansengaging said pulsing cams for holding said elements in said selectedposition, a manually operable bar for actuating said holding means fordisengagin them from said pulsing cams for permitting the returnmovement of said elements to normal collectively, motor springstensioned by the movement of said elements toward selected position, apulsing mechanism disposed for operation by the cams of said elements, agovernor mechanism for controlling the return movement of said elementsunder the tension of said motor springs and means for negativing thecollective return movement of said elements to normal non-operatedposition as for cancelling a call.

4. In a call transmitter, a casing having a cradle for receiving atelephone handset, a shaft, an arcuated manually operable elementmounted for free rotation on said shaft, said element having a pluralityof pulsing cams formed at its inner periphery, a contact, a mechanismdisposed for operation by said cams for actuating said contact, anarcuated dial secured to said element, said dial having fin membersserving for moving said element from normal to selected position, amotor spring tensioned by the movement of said element, means engagingsaid pulsing cams for holding said element and said dial in saidselected position against the tension of said motor spring, a manuallyoperable mechanism for actuating said means for releasing said elementfor permitting the latter to return to normal position for actuatingsaid mechanism, a mechanism operable upon the removal of the telephoneset from its supporting cradle for locking said means in disengagedp'ositionfrom said pulsing V a cam during the return movement of saidele-- ment, the last-mentioned mechanism releasing said holding means tocause the latter to reengage the pulsing cams upon the placing of thetelephone handset in its supporting cradle. 1

5. In a call transmitter, a plurality of pulsing elements movable inposition for setting a call, a dial carried by each of said pulsingele-, ments for indicating such call, motor means for returning, saidelements from selected to normal position, a bar disposed for engagementwith 10 and an off-normal contact controlled by the operation of saidother cams.

RUDOLPH F. MALLINA;

